SYRINGE WITH SQUEEZE RELEASE NEEDLE GUARD

SERINGUE AVEC GARDE-AIGUILLE A LIBERATION PAR PRESSION

English Abstract

A syringe (10) for drawing blood from a patient, the syringe haying a
barrel (12) with a restricted free end (12a) and a needle assembly (14)
releasably secured
to the restricted free end. A plunger (16) is inserted into the barrel through
an opposed
end (12b), and retraction of the plunger within the barrel, away from the
restricted free
end is effective to withdraw blood from the patient when a needle (14a) with a
sharpened
free end of the needle assembly is appropriately inserted into the patient.
The syringe 10
is also provided with an annular needle guard (18) that surrounds the barrel
and is
slidable with respect thereto between a first position, in which the needle
guard does not
surround the needle, and a second position, in which the needle guard does
surround the
needle, to prevent the tip of the needle from injuring a person handling the
syringe during
times when the syringe is not being used to withdraw blood from a patient. The
needle
guard is made from a semi-rigid, transparent organic material, and has a
diametrically
opposed pair of inwardly extending projections (18a) that engage a
diametrically opposed
pair of outwardly facing recesses (14a) in the needle assembly when the needle
guard is
in its first position to prevent it from inadvertently moving to its second
position. Hand
squeezing of the needle guard along an axis extending perpendicularly to an
axis between
the projections is effective to disengage the projections and recesses,
whereupon relative
motion can occur between the barrel and the needle guard. This will occur, by
gravity, if
the syringe is held in a substantially vertical position with the needle up,
whereupon the
barrel will fall relative to the needle guard until the second position of the
needle guard is
reached.

Claims

7
What is claimed is:
1. A blood drawing syringe comprising:
a barrel;
needle means connected to an end of said barrel;
a plunger positioned within said barrel, said plunger being slidable
within said barrel away from said needle means:
a needle guard formed of a squeezable semi-rigid organic material
surrounding said barrel, said needy guard being slidable with respect to said
barrel from a
first position, in which said needle guard does not surround said needle
means, to a second
position, in which said needle guard does surround said needle means; and
~ locking means normally retaining said needle guard in said first
position with respect to said barrel, said locking means comprising radially
projecting
means on one of said needle guard and said needle means and radially facing
recess means
un the other of said needle guard and said needle means, said radially
projecting means
normally engaging said radially facing recess means to prevent said needle
guard from
moving with respect to said barrel, said spaced apart radially projecting
means and said
radially facing recess means being disengagable, after drawing blood from a
patient, by
squeezing said needle guard to disengage said radially projecting means and
said radially
facing recess means to permit said needle guard to move with respect to said
barrel from said first position to said second position, such disengagement
being capable of
accomplishment by a step that only requires action by a single hand of a user.
2. A syringe according to Claim 1 wherein said radially facing recess
means comprises a diametrically opposed pair of recesses and said radially
projecting
means comprises a diametrically opposed pair of projections.

8
3. A syringe according to Claim 2 wherein said needle means
comprises said diametrically opposed pair of recesses and said needle guard
comprises
said diametrically opposed pair of projections.
4. A syringe according to Claim 1 wherein said semi-rigid organic
material is transparent.
5. A syringe according to Claim 3 wherein said needle guard has a
first end and a second end, wherein said diametrically opposed pair of
projections of said
needle guard is adjacent said one of said first end and said second end, and
where in the
other of said first end and said second end of said needle guard has means for
frictionally
engaging said needle means in said second position of said needle guard.
6. A syringe according to Claim 5 wherein said means for frictionally
engaging comprises, at said other of said first end and said second end of
said
needleguard, thickened portion and a diametrically opposed pair of pair slots
extending from a free end of said other of said first end and said second end
of said
needle guard partly to said one of said first end and said second and of said
needle guard.
7. A needle guard according to Claim 6 wherein said radially
thickened portion has means on an interior surface for engaging means on an
exterior
surface of said needle means for preventing rotation of said needle guard with
respect to
said needle means in said second position of said needle guard.
8. A syringe according to Claim 7 wherein said moans on an interior
surface comprises a splined surface and said means on an exterior surface
comprises a
complementally splined surface.

9
9. A syringe according to Claim 1 wherein said semi-rigid organic
material is mainly comprised of clarified polypropylene and wherein said
needle guard is
transparent.

Description

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SYR1NGE WITH SQUEEZE I~LEASE NEFDLG GUARD
BACKGRO NI7 ~ THE 1NVFN~rION
1. FIELD nF THE INVFN°f(ON
This invention relates to a syringe of the type used to draw blood from a
patient. More particularly. this inventicm relates to a syringe of the
foregoing character
which has a telescoping needle guard that is relented by squeezltag, after the
draw-ixal; of
blood iTOm the patient, to protect medical perac~nnel frorn injurious contact
with a sharp
tip of the needle that is a part of such a syringe.
2. pESCRIPTIUN OF THE PR10R A,RT
Various types ot~ syringes with telescoping needle guards arc described in
various issued patents, For example, in IJ.S. Patent 4,897,083 (Marten), LJ.S.
Patent
5,338,303 (King et al.) and U_S- Patent 5.338,310 (Lewundowski). .A
characteristic of
these and other types of blood drawing syringes with telescopic needle guards
is that the
pers«n using any such syringe must use two bonds to telescope the guard
relative to the
syringe, after using the syningc to draw blood from a patient.
SUMMARY OF TH~,1NVLNTIO~1
A blood drawing syringe according to the present invention has an annular
needle guard that surrounds and is telescopic with respect to the exterior of
the body of
the syringe. the nceule guard being retracted fwm surrounding contact with a
needle of
the syringe during the use of the syringe to draw blood arom a patient. The
guard is
rrtattufactured ft'Om a transparent organic material to pr.~rmit capacity
graduations on the
needle to be read by the user, and it has suiF~cier<t tlcxibility to be
distortable 1n its

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configuration under the pressure of a single hand uEtha user, In its
unsyueezed cotldition.
the sleeve has 3 series of spaced atpart inwardly projection luga that are
received In a
corresponding series of inwardly extending recesses c~f a needle containment
titm.ettt at
the end of the syringe barrel to positively retain the sleeve in a position
where it does not
interfere with the use of the syringe. F-Towevcr, squeezing of the sleeve will
distort its
shape to the point that its lugs due not engage the fitment, and then the
needle can readily
move to a position relative to the sleeve where the needle will be guarded,
and will dv 50
by gravity if the syringe is held vertically with the needle up. Thus. the
requisite relative
motion between the needle :end the ~le~:ve, from the original locked position
of the sleeve,
where the sleeve does not guard the needle, to the guarding position of the
sleeve can be
accomplished by a step that only re9uires action by a single hand of the user.
Accordingly, it is an ubjcct of the present invention t0 provide an
improved blood drawing syringe. More particularly-, it is an object of the
present
invention to provide a blood drawing syringe of the foregoing character in
which the
needle of such syringe can be readily guarded, after the drawinb «f blood, to
prevent
accidental contact of an exposed needle by pcrsonr,el involved in its
handling. Even
more particularly, it is an object of the present invention to provide a blood
drawing
syrinbe of the foregoing character in which the suarding of the needle is
acconrtpllshed by
a sleeve that is provided with a syringe and is moveable relati«e to a barrel
of tlae syrinec
from a positron whore the sleeve does not guard the needle to a position where
the sleeve
does guard the needle.
Por a further understanding of the present invention and the objects
thereof, attention is directed to the drawing and the following brief
description thcrcvE, to

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17?44
the detailed description of the preferred embodiment vf~thc invention, Rztd to
the
appended claims.
1:3RIL;F DESC'RIP'CZc7N OF THL DRAWING
F1G. i is a perspective view of a syringe according to th.e preferred
embodiment of the present invemion in its pvsitic~n, after usage;
FICi. 2 is an elevational view, in cross-section and at an enlarged scale, of
the syringe of FIG. 1 in a position of sui;h syringe; when ii is ready for
use;
FIG. 3:is a view Likc fICJ. 2 of the syringe of FIGS. 1 and 2 after
completion ox its use:
flG. 4 is a sectional view taken on line 4-4 of FIG. 2; and
F1U. 5 is a sectional view taken on line 5-5 of >'rIG. 3.
DF't"AILL;D DESC:RIPTIUN OF THE PREF)rRRED EI~ROI)IMEN'L
A syringr according to the preferred embodiment of the present invention
is identified generally by reference numeral 10, and the syringe l 0 includes
an annular
molded plastic harrel 12 with a needle assembly 14 removably secured to a
restricted free
end 12a of the barrel and a plunger 16 that is slidably inscrccd in an opposed
and 12b of
the barrel 12, the opposed end 12b having an oppvsrd set of outwardly
projecting tabs
12e to facilitate handling of the Syringe I U. The ptun~cr 16 has a
cylindrical portion 16a
at a flee end that is within tht barrel 12, and sCrveS to draw blood fronca a
patient through
the needle assembly 14 when the plunger 16 is drav~na away from the needle
assembly 14.
In that regard, the plunger 16 has an enlar~cd gripping portion 16b at an
opposed end.
While the plunger 16 is slldable with respect to the barrel 13, there is very
little clearance
between the outside diameter of tha cylindrical portion 16a and the inside
diameter of the

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t72d4
btwrel 12, to thereby ensure that the retraction cif the plunger 16 will be
effective to create
the negative pressure that is needed to withdraw hluod from a patient. The
barrel 12 is
also provided with an annular extension 12c that ,urrounds a portion of the
restricted free
end 12a and detincs an annular space with the restricted tree end 12a. The
annular
extension 12c has a helical thread 12d un its inside wall by which the needle
assembly 14
is thereby releasably secured tv the barrel 12. The annular extension 12c with
the helical
thread 12d is of the type shat is referred to as a "standard locking luer" and
conforms to ate
.ANSI/liTMn MA 7U.1 - 1983 specification.
The xyrinse 1. fl i~ also prnvided with an anaaular needle guard 1$ that
surrounds the b~~rrel 12 ofthe syringe 10 and is slidable with respect to the
barrel 12
between a first position, as shown in FIGS. l and 3, where the needle guard.
surrounds a
needle element 14a of the needle assembly 14 to prevent contact between a
sharpened
free end of the needle laa and any person involved in handling the syringe 1
U, and a
second position, as shown in FIG. 2. which is its initial position, yvhcrc the
needle guard
i 8 is well away from surrounding contact with respect to the needle 14a of
the needle
assembly is tv permit the user to properly usa the syringe 10 to draw blood
from a
patient. In that regard, the z~eedlc guaurd 18 is preferably molded from a
suitable
transparent organic matet~al to permit a user t« inspect any volumetric
markings on the
barrel 12 (not shown) and to detctminc if zny blood splashing is occurring
during the
drawing of blood. The needle ward 18 is also of a semi-rigid material to
permit it to be
temporarily distorted liom its original circular configuration, under hand
pressure, for
reasons that will be hereinafter explained more fully. A gamma ray sterilized,
clari~'ted
polypropylene is a suitable resin for the manufacaure of she needle guard to
permit it to

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1?~44
properly pGrlorm all required functions. and it is pre;fen-ed that such needle
guards be
paeka6ed in bliater packs and then sterilized befi~re shipment tv users- In
any case, it is
preferred that the needle guard 1 !3 and the barrel 12 be fonn.cd of
dissimilar organic
materials to tiwoid binding than c2n occur when like organic elements must be
moved
relative to one another.
I~he needle assembly 14 is pravidcd with a diametrically opposed pair of
inwardly extending recesses 14b tlaat receive a diametrically opposed pair of
inwardly
~;xtending projections,t 8a of the needle guard 18, when the needle guard 1 S
is at its
innermost, non-guarding position. as shown in FIGS. ? and 4, to prevEnt
inadvertent
movement of the needle guard 18 to its guarding; position Of FI~i.,3. However,
by the
application c~f hand pressure to the needle gmrd 1 R at opposed locations,
along an access
that extends perpendicularly to the axis that extends hetween the projections
18a, the
projections 18a will disengage from the reces.:es i4a to allow the needle
guard 18 to
move to its gutwding position. This can happen at the conclusion of the blood
drawing
process if the user grasps the syringe 1 U at a location along the axis that
extends
perpendicularly to the axis between the projections 18a, which can be done in
zr one-hand
motion, and if this is done while the syringe lU is held in a substantially
vertical position
with tha needle l4a pointing up, this will happen by gravity as the barrel 12
then retracts
ralati~~e to the needle guard 18. At that time, an added tr-tnipulativc step,
which can be
performed by hand may be required to ensure that the needle Guard 18 has
frictiotaally
locked into its Pig. 3 guarding position. In the guarding position of the
needle guard x A
relative to the barrel 12, the needle guard t 8 is frictionally held in
position relative to the
barrel 12 by an interference fit between a thickened free c:nd 18b of the
needle guard 18

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chat is oppc~scd to the and with the projections 18a and an exterior surtac~
of the needle
assembly l~, the end 18b being provided with an opposed pair of ,lots 18c that
extend
partly from the free end 18b toward the projections 18a to permit the free end
18b to
expand to the extent necessary to cecurely grip the needle assembly 14.
~rurther, the
inside surface of the and i 8b of the needle guard 1$ is preferably aplined
and the exterior
surface of the needle assembly 1 a, at the location of its engagement with the
end 18b of
the Needle guard 18 in the guarding position ef the needle guard 1$, is
cumplementally
splined to prevent relattive rotation between the needle guard 18 and the
barrel 12 in the
guarding position ox the needle ward L 8, other them to unscrew the needle
assembly 14
from The barrel I2 when desired.
It is also contemplated that the syringe 10 can be provided with a separate,
removable sheath (nvt shown) to cover the needle 14a in itc Fig. 2 conditiotl
until the
syringe 10 is ready for use ttnd with an elastvmeric plug (also not shown) to
be inserted
intro the restricted free end 12a ufthe barrel, after the use ofthe syringe 10
tv draw blood,
and the needle assembly 14 is ready to be unscrewed from the barrel 12, as
described
;hove until the filled syringe 10 is ready to be enrtptled.
Although the best mode contetxtplated by the inventor for carrying out the
invention as of the filing date hereof has been shown and described herein, it
will be
apparent to those skilled in the art that suitable ttnoditications, variations
and equivalents
may be made without departing liom the scope of the invention, such scope
being limited
solely by the terms of the following clalrns and the legal equivalents
thereof.

Representative Drawing